Scant research has examined the mental health of migrant farmworkers in the United States. The purposes of the present study were threefold: to assess the prevalence levels of anxiety symptoms in a sample of Mexican migrant farmworkers in the Midwest United States; to examine the relationship between acculturative stress and anxiety; and to determine the variables that significantly predict anxiety. High levels were found for overall anxiety and in the cognitive, affective, and physiological expressions of anxiety. Elevated acculturative stress, low self esteem, ineffective social support, lack of control and choice in the decision to live a migrant farmworker lifestyle, low religiosity, and high education were significantly related to high anxiety levels. The overall findings suggest that Mexican migrant farmworkers who experience high acculturative stress may be at risk for developing anxiety-related disorders. The findings highlight the necessity of establishing prevention and treatment services for migrant farmworkers that increase levels of emotional support, self esteem, and coping skills.